When crimping a 70-square copper nose, you can't use ordinary line pressing pliers, but you need hydraulic pliers. If there is no hydraulic clamp, it is not recommended to hit it with a hammer. The copper nose punched with a hammer is easy to be pressed tightly, which will affect the conductivity in the later stage and there will be some hidden dangers. Check the firmness after crimping with hydraulic tongs to see if the wires are loose.